How do I check and replace engine oil sensor.

Different engines can show different values. Sometimes it is the sensor itself that causes the variation. The pressures that you are witnessing are well within operation norms and are nothing to be worried about. As long as you don't experience severe drops in oil pressure during acceleration and deceleration, then the oil pressure system is working well.

the oil pressure hot on your test gauge will be below recommended pressure necessary for the proper lubrication of the engine . The control module as you say will be set higher to notify you before that pressure is reached so that there is sufficient time to shut down the engine

Problem could be a bad oil pressure sensor or the oil pump is failing. A mechanical oil pressure gauge needs to be hooked up to verify actual oil pressure. Problem could also be a bad stepper motor in the instrument cluster that drives the gauge.

Well it could be the sending unit for the gauge.
But odds are the oil pump or engine bearings are worn out.
As the engine warms up, the metal spaces expand and the oil gets thinner. The oil pressure drops some under normal conditions, but not more than 10 or 15psi. Normal idle pressure with the engine warmed up is probably 25psi.
You could check oil pressure with a mechanical gauge to make sure its not the sending unit.
Once the oil pressure starts staying below 20psi for long periods you'll start hearing noises.

You need to pull the pressure sensor and install a manual test gage, (borrow from Autozone or other chain part store) that is the only way to verify the engine is not loosing oil pressure.

Pressure regulator on the oil pump time for a new one

Very first thing you need to do is install a mechanical pressure gauge on there to verify what you see on your gauge. If the actual pressure is low, then it's time to start looking inside the engine. If not, then you need to trace out the electrical problem but will know the engine is safe.

Hello mb4494: My name is Roger and I will help you. If by changing the oil pressure sending unit the problem did not change. I would perform a oil pressure test. This is done by removing the oil pressure sensor and inserting a oil pressure gauge. This can be done by yourself or by a repair shop. This needs to be done on a cold engine. Start the engine and observe the oil pressure cold.as the engine warms up observe the pressure. The pressure will drop off as the engine warms up.Should the oil pressure drop below 10 to 12 PSI. then you have internal engine trouble. More then likely a bearing problem. Try dropping the truck into gear and see what the pressure drops off to. Again if the pressure drops below 10 to 12 PSI. you have a problem. I would also check to make sure you have the correct oil switch. a truck with a oil light uses a oil pressure switch. with a gauge you would use a oil pressure sending unit. Sorry for the long reply but want to make sure you check the pressure correctly. Please rate the quality of the answer as this is how we know the answer was correct. Thank You for using Fix Ya. Roger

The pressure to be most concerned with is the reading in gear at idle with engine warmed up...Low end really should not be below 20. If pressure wanders, change the sending unit and check actual pressure with a mechanical gauge if necessary. The age and quality of your oil, as well as temperature all play a part in pressure, as well as internal wear from time & miles of use. If pressure changes with rpm, that is normal. 40psi is good while driving.
need more info just ask.

yes, I would not do anything as long as you do not hear any unusual noise in the engine ,